Sound-box



J. H. ELLIS.

SOUND BOX. APPLICATION FILED mu 25. 1918.

Patented Mar. 1, 1921.

' between a shoulder 13 of t e sound PATENT omen.

JAMES H. ELLIS, 0! MILWAUKEE, WISCONSIN, ABSIGNOR OF ONE-HALF T0 JOHN BCHUSTEB, OF MILWAUKEE, WISCONSIN, AND ONE-HALF T0 L. E. COLLINS, 0F

KINGS HILLS, OHIO.

sown-no:

Patented Mar. 1, 1921.

a lication flied m 25, ms. Serial no. 24 ,099.

reproducing instruments, with the dia; phragm retaining r1 (1 formed in sections and clamping the diap iragm with different pressures at different )arts.

Another object of the invention is to pro vide such a variable pressure sectional clamping ring associated with a diaphragm having its stylus connection out of center and the portion of its edge nearest the stylus connection under greater ressure.

Another object o the invention is to provide a diaphragm with a stylus connection of mica having the needle arm passed therethrough with a rubber insulation therebetween.

With the above and other objects in view the invention consists in the sound box as herein claimed andall equivalents.

Referrin to the accom anying drawings in which li e characters 0 reference indicate the same parts in different views:

Figure 1 is a plan view of a sound box constructed in accordance with this invention, parts being broken away to show their arrangement;

gig. 2 is a central sectional view thereof; an

Fig. 3 is a sectional view of the diaphragm.

In these drawings 10 indicates the recessed cu memberof the sound box which is of suitable material, preferably vulcanized fiber. The diaphragm 11, preferably of vulcanized fiber, is contained in the cavity of this sound box between rubber gaskets 12 and its edges are clam d with 'ressure on ,and a clam ing ring 14 which is secured to the sound ox by means of screws 15. The clamping ring 14 has an arched guard or bridge 16 extending across it. The ring is cut in two along lines 17 at one sideof the bridge so that the sector on which the needle arm 18 is pivotallymounted is entirely independent from and out of contact with the ot er sector carrying the bridge.

'A. stylus connection 20, preferably con sisting of a piece of sheet mica, is secured to the diaphragm by having its edge passed through a slit in the diaphragm and cemented thereto on both sides of the diaphragm and it is connected with the needle arm by havin the narrow reduced end of the arm passed throu h an opening therein, a short section of smaii rubber tube 21 fitting on said end of the needle arm to constitute insulation between the needle arm and the stylus connection.

The flange portion of the clamping ring, which bears on the gasket 12 to clamp the edge of the diaphragm is deeper on that section of the ring'whic carries the needle arm and as both sections are clamped by their screws 15 until they tightly bear on the edge of the sound box,'the pressure with which the edge of the diaphragm is held by such ring section is eater than the pressure with which the iiii iphragm is held by the opposite section. As the eccentrically positioned stylus connection is nearer the needle arm, it is the shorter ortion of the diaphragm, measured from the stylus connection to the edge, that is-clamped with greater pressure b the section of the 'ring on which the need e arm is mounted.

The more tightly clam ed ortion of the edge of the diaphragm, w rich 5 at the samev time the portion nearer to the stylus eonnection, is believed to respond more completely to the high notes, while the other portions of the iaphragm respond more completely to the low notes, so that the same sound box me be used for all records and all parts of t e record will receive their pro er relative value.

e stylus connection of sheet mica serves to give the desired flexibility to permit of the absence of pivotal connections and still faithfully transmit the motions. The rubber tube forms'an insulation between the diaphragm connection and the needle arm, while the cement connection of the stylus connection with the diaphragm prevents nelative movement between these parts.

I desire it to be understood that this invention is not limited to any specific form or arrangement of parts except in so far as;

such limitations are specified in the claims.

The use of a, rubber tube as insulation between the stylus connection and" the needle arm SeIfVpS tie purpose of securely holding the mica against splitting, the ends of the tube flaring while the middle portion is contracted forming in efl'eet a rivet.

What I claim as new and desire to secure by Letters Patent is:-

1. In a sound box, a diaphragm-retaining ring formed in sections. I 2. In a sound box, a diaphragm-retaining ring formed in sections, one section serving to clamp the diaphragm tighter than the other section.

3. In-a sound box, a diaphragm'aetaining ring formed in sections and provided with a bearing flange for clamping the diaphragm, the hearin flange on one section of the clamping ring bein deeper than the hearing flange on the otiier to bear with greater pressure on the edge of the diaphragm.

4. In a sound box, a diaphragm-retaining ring having an arched bridge portion extending across it to form a uard for the stylus connection, said rin eingsplit at opposite points at one side 0 the bridge, and

fdl' needie arm pivotaiiy mounted on the seetion of the ring that is without the bridge.

5. In a sound box, the combination, with the diaphragm, of diaphragm -rlamping means, said means serving to clamp one section of the diaphragm tighter than the other.

6. A sound box comprising a cup-shaped member, a diaphragm fitting therein between gaskets, a retaining rin secured to the fare of the euphaped member and brovided with a flange extending within the cavity of the cup-shaped member and hearing on one of the gaskets for clamping the edgeof the diaphragm, said ring be ng split at opposite points to divide it into sections, the bearing flange on one section being, deeper-than that on the other, an arch-like bridge connecting the ends of the last mentioned ring section, and a needle arm pivotally mounted on the first mentioned ring section and connected with the diaphragm.

In testimony whereof, I aiiix my signature in presence of two witnesses.

' JAMES H. ELLIS.

Witnesses: I

R. S. G. CALDWELL, Gns'mv E. HOLMES. 

